Machine for forming reinforcing ribs on container covers



H. F. DRNEC Dec 31,- 1957 MACHINE 1 0R FORMING REINFORCING RIBS oN CONTAINER COVERS 5 Sheets-Sheet 1 Filed April 24, 1956 mlw .fzz veh 'af .Drrzec H. F. DRNEC MACHINE FOR FORMING REINFORCING RIBS ON CONTAINER COVERS Filed April :24, 1956 5 Sheets-Sheet 2 MACHINE FOR FORMING REINFORCING RIBS ON CONTAINER COVERS 7 Filed April 24, 1956 H. F. DRNEC Dec. 31, 1957 5 Sheets-Sheet 3 f'zuerzfof yfi rzziec Dec. 31, 1957 H. F. DRNEC MACHINE FOR FORMING REINFORCING RIBS ON CONTAINER COVERS '5 Sheets-Sheet 4 Filed April 24, 1956 Dec. 31, 1957 H. F. DRNEC 2,818,005

MACHINE FOR FORMING REINFORCING RIBS ON CONTAINER COVERS Filed April 24, 1956 5 Sheets-Sheet 5 United States Patent MACHINE FOR FORMING REINFORCIN G RIBS ON CONTAINER COVERS Harry F. Drnec, Chicago, 11]., assignor to Container Corporation of America, Chicago, Ill., a corporation of Delaware Application April 24, 1956, Serial No. 580,321 6 Claims. (CI. 93-49) The present invention relates to container forming mechanism and more particularly to a machine of this character for the formation of a reinforcing flange or rib on the edge of a cover member of a paperboard container, such as disclosed in the United States Patent to George W. Boh Patent No. 2,167,741,. dated August 1, 1939.

A principal object of the invention is to provide an efficient, effective an economical machine for conveying and guiding a partially formed container, provided with one or more cover flaps, past cover reinforcing rib-treating or shaping elements to bring the cover .and reinforcing rib-forming parts into their final assembled relation and to accomplish this result in asmooth and continuous movement whereby the container cover reinforcing rib,

will be formed accurately and rapidly.

Other and more specific objects and advantages of the invention become apparent in the description which follows.

Cover reinforcing flanges or ribs of' the general type illustrated in the Boh patent have been formed by stapling, or by gluing theparts by hand operation, to the,

underside of the container cover. This hasbeen. a relatively slow process and difficulties havev been encountered due to inaccuracies occurring in. the assembly and joining of the parts. Mechanism has also, been employed for holding the container in a stationary position while mechanical pressure is applied to previously glued flangeor rib forming parts to bring them to. the desired relation and so hold them while the glue hasset. The present invention provides improved mechanism in which the gluing, forming and holding of the cover rib-forming elements is done as a smooth and continuous operation.

The container with which the machine of the present invention is particularly adapted tooperate is preferably formed as an open ended tube with top and bottom closure elements or flaps extending from the free edges of the side and end walls. The top closure members on the side walls have extended portions at their free ends which when brought into folded relation form cover .reinforcing ribs.

The mechanism of the present inventionin its preferred form includes essentially .a, conveyor for supporting the container in upright position and with top closure flaps extended laterally outward of the container. As the container is carried on the conveyor a suitable adhesive is first applied to one. ofthe surface portions which are to be secured together. The covermembers with the extended rib-forming portions are, then moved along cam surfaces which fold the rib-forming parts into the desired relation to each other and to their attached cover member. When the parts have, been brought approximately to their final relation, the cover members will be brought to closed-position and at this point the reinforcing ribs are preferably forced into a suitable groove or opening in a mandrel that-was placed within the container at the receiving end of'theconveyern The.

container thus brought to its completed formis carried ICC . 2 along further under suitable top pressure until the adhesive has become set, after which the cover members are raised, the mandrel is removed and the container is ready to receive contents, such as filled beverage bottles.

In the drawings illustrating a preferred embodiment of the invention:

Figure 1 is a view in side elevation of the upper portion of the machine showing approximately one half of the length of the conveying and forming mechanism from the receiving end to the mid-portion, certain of the frame parts being omitted for clarity of illustration;

Figure 2 is a View in side elevation illustrating a con tinuation of the portion shown in Figure 1 extending from the mid-portion of the machine to the discharge portion and illustrating a part of the pressure section which is to hold the parts in proper relation until the adhesive has set, certain of the frame parts being omitted for clarity of illustrations;

Figures 3 and 4 are plan views of the parts shown in Figures 1 and 2 respectively;

Figure 5 is a front elevational viewtaken partly in section along line 55 of Figure 1, looking in the direction of the arrows, and showing the receiving endof the machine;

Figure 6 is a vertical sectional view taken along line 66 of Figure 2, looking in the direction of the arrows, and showing the parts at the discharge, end of the ma chine;

Figure 7 is a perspective view, of a container having cover members with reinforcing, ribs which the machine of the present invention is designed to form;

Figure 8 is a perspective view of a preferred form of mandrel designed for use in aiding in the formation of the reinforcing ribs;

Figures 9 to 17 inclusive are schematic views illustrating the various positions assumed by the trailing edges of the container covers and reinforcing ribs thereon as they appear at difierent stages in the progress of the container through the machine, the lines on which such views are taken being indicated by section lines corresponding to the figure numbers;

The container C for which the mechanism of the present invention is designed comprises, as herein illustrated, a body portion formed of side walls 5, Sand end walls 6, 6 arranged in tubular form and joined at one corner by an attaching flap 7. The bottom of the container is preferably formed by two sets of overlapping closure flaps, as shown in the above mentioned Boh patent. The top closure of the container is formed of two panels 8, 8 on the top edges of the side walls. Extending from these panels are sections 9, 10 and 11, preferably defined from the cover panels and from each other by longitudinal score lines 12, 13 and 14, The section 11 of each cover is preferably secured to the underside of the closure by means of glue or other suitable adhesive. The reinforcing rib R formed by the section 9, 10 and 11 is arranged so as to be received into the upper portion of the container and the edge portions of the closures adjacent the ends of the container are so dimensioned as to rest upon the upper edges of the end walls. By dimensioning the reinforcing ribs so as to fit relatively snugly between the container end walls considerable resistance will be aiforded against distortion of the upper part of the container when the closure panels .are in closed position.

The mechanism of the present invention is supported on suitable frame members, certain of which are illustrated in Figs. 5 and 6. Vertical members 20, 20 and 211, 21 are connected to each other by longitudinally extending members 22 and 23 and transverse angle members 24 and 25. The members 22 and 23 preferably extend the entire length of the machine. A suitable number of adte tedpsa 31, 1957 ditional vertical members, similar to members 20 and 21, and transverse members similar to members 24 and 25, not shown, are employed along the length of the machine to give it the desired strength and rigidity.

The container C in expanded condition is carried through the machine from the receiving station, or front of the machine, at the right end of Fig. 1 to the discharge point, or rear of the machine, at the left end of Fig. 2. For the purpose of carrying the container through the machine a plurality of rollers 26, 26 are employed upon which the container is supported and oppositely disposed endless belt conveyers 27, 27 areprovided, adapted to engage the sides of the container with a frictional grip and carry it along with a more or less positive action. Rollers 28, 28 mounted to rotate freely-on vertical axes, are located to bearupon the inner surfaces of the belts 29 to hold the belts in firm contact with the container sides.

The rollers 26 are journalled to rotate freely and are supported on frame elements 30 secured to transverse frame members 24. Y

The conveyer belts 29, 29 pass around vertically journalled pulleys 31, 31 at the receiving end of the machine and pulleys 32, 32 at the discharge end. The pulleys 31, 31 are mounted on shafts received in upper and lower bearing blocks 33, 33 arranged in longitudinally extending members 34 which are supported on the transverse frame members 24. The bearing blocks 33, 33 are preferably provided with grooves to receive guide elements to enable the blocks to move longitudinally for the purpose of adjusting the tension on the belts 29.

The pulleys 32, 32 are each mounted on driven shafts 36, 36 received in upper and lower bearings 37, 37 secured on the longitudinally extending members 34, 34 at points remote from belt pulleys 31, 31. The rear ends of the members 34, 34 are supported on the transverse frame member 25. The lower end of each shaft 36 has keyed thereon a bevel gear 39 meshing with a similar bevel gear 40 splined on shaft 41 which has its ends journalled in bearings 42,. 42 mounted on the longitudinal frame members 22, 22. The shaft 41 may be driven by means of a suitable motor and gearing, not shown, connected with the gear 43 keyed to shaft 41. The shank portion 44 of gear 40 is grooved and held against endwise movement by a plate 45 suitably slotted to fit Within the groove of the gear shank. The plates 45 are each bolted onto the bottom of the longitudinal members 34.

For the purpose of adjusting the belt conveyers 27, 27 bodily toward and from each other to accommodate different sizes of containers, the longitudinal conveyer supporting members 34, 34 are slidably supported on the transverse frame members 24 and 25. Additional plates 46, 46 extend downwardly from the members 34, 34 adjacent to the plates 45 and have threaded blocks 47, 47 secured thereto, through which reversely threaded portions on a rotatable rod 48 extend. The end portions of rod 48 are received in bearings in the longitudinal frame members 22 and 23. By turning the rod 48 in one direction on the other the frame members 34, 34 may be moved toward and from each other.

The front ends of the members 34, 34 may be likewise adjusted toward and from each other by a similar rotatable rod 51 having threaded portions received in threaded blocks 52, 52 each secured to a depending plate 53 attached to the respective member 34, 34.

As illustrated in Figs. 1, 3 and 5, the container, the cover flaps of which are to be formed, is first placed with its bottom portion resting on a receiving plate 56 with the cover members and unformed reinforcing rib portions extending laterally outward of the container. After the container has been placed on the receiving plate 56 there is preferably introduced into the container a mandrel 57, which is of such size and shape as to fit snugly within the container.. The mid portion of the top of the mandrel is preferably formed with a longitudinally extending groove 58 of generally rectangular shape in cross-section to receive the newly formed reinforcing ribs on the cover portions. In practice it is preferred to have a separate groove portion for each reinforcing rib, and for this purpose an upstanding part 59 is provided extending the length of the groove 58. Finger openings 60 are provided for convenient handling of the mandrel.

With the covers and the extended portions thereon in laterally extended position the container is then moved into position where it will be gripped and carried into the machine by the friction surfaced conveyer belts.

The container will first be carried past a gluing station where a narrow band of adhesive will be spread on one of the two portions which are to be adhered. In the present instance a band of liquid adhesive is applied to portions of each of the two upwardly presented, outwardly extending covers. It will be understood that such up wardly presented cover surfaces become the under surfaces when the closures are in closing position.

Referring to Figs. 1, 2, 5 and 9 the glue-applying rolls 62, 62 are each mounted on short shafts 63 having their ends rotatably supported on depending legs of frame members, indicated as a whole at 64, each of which is swingably supported on a driven shaft 65 having its ends supported in bearings carriedby the upright frame members 20, 20. The glue roll shafts 63 are suitably driven by means of a sprocket keyed thereon around which passes a sprocket chain 66 which also passes around a sprocket keyed to the shaft 65. A glue pot 67 is supported by each frame member 64 in position to feed glue to the glue roll. Rotation of the shaft 65 by suitable driving means, not shown, will cause rotation of the glue rolls.

A small idler roller 68 is supported just beneath each of the glue rolls upon frame elements mounted on the longitudinal supporting members 34 for the container conveyer. These idler rollers are adapted to contact the lower surfaces of the extended covers and hold the upper surfaces of the covers against the glue roll.

To assure proper positioning of the container as the covers pass beneath the glue rolls additional idler rollers 71, 71 are employed. These rollers are carried by a centrally disposed supporting member 72 which will presently be described more fully. There are preferably two rollers 71 on each side of the member 72. These rollers project somewhat below the lower edge of this member whereby they are adapted to come into engagement with the top surface of the mandrel 57 along the sides of the groove 58. o

After adhesive has been applied to the cover members at the desired location the cover members are ready for the reinforcing-rib forming operation, the mechanism for which will now be described.

In the present machine it is considered desirable and most efficient to treat both cover members in an identical and simultaneous manner, although this is not essential. For simplicity, the following description will be limited where possible to the mechanism for treating only one of the cover members.

In order to facilitate the entry of the outwardly extending portions that are to form the cover flaps in between glue-applying roll 62 and idler roll 68, a pair of guide rods 69 and 70 are suitably secured to the frame of the machine. The end portion of guide rod 69 is curved upwardly and the end portion of guide rod 70 is curved downwardly to form between them a flaring mouth portion to receive the cover sections being introduced therebetween.

In order to shape the reinforcing ribs in the desired manner guide bars or plows 73, 74, 75 and 76 are secured along the sides of the center frame member 72. This member is preferably supported for vertical adjustment on transverse bars 79 having their ends secured in upright frame members 21.

As soon as the trailing edge of the cover 8 has cleared &181995 the glue roll the cover is preferably swung upwardly by riding on the cover raising guide bar 73 which, asshown in Figs. 1 and 3, is inclined upwardly and inwardly. This guide bar is suitably secured near its front and lower end to the frame portion 34 by means of a short stud 80 welded or otherwise attached to such guide bar. At its rearward and upper end the guide bar 73 is for convenience joined with guide bar 75, and the two bars at their point of connection are attached to a laterally extending leg 81 of a bracket having an upwardly directed portion 32, slotted for the reception of a connecting bolt to enable the bracket to be secured to the center frame member 72 at different vertical positions.

At a place where the cover has been raised through a desirable maximum angle the guide bar 74 is positioned so as the container traverses the machine the bar 74 will engage against the inner surface of the cover. See Fig. 10. Each bar 74 preferably has a threaded end 86 passing through openings in the frame member 72 and adjustably secured with nuts on each side of such member. The bar 74 is also preferably arranged in a sub,- stantially horizontal plane, that is it is arranged parallel with the container conveyer and, through the major portion of its length, the bar 74 is inclined outwardly and preferably crosses the vertical plane of the bar 73 at a point in front of the juncture of bar 73 with bar 75. At a point beyond the juncture of these bars the bar 74 has a section 74a which is inclined laterally toward the frame member 72. The bar 74 is supported near its mid-portion upon the frame member 72 by means of an adjustable bracket member 87 having an upstanding portion 88 arranged to be bolted onto the member 72. See Fig. 3. i

As the container is carried from the point at which Fig. is taken to the point at which Fig. 11 is taken two actions preferably take place-the cover 8 is caused to incline outwardly and the extended portion, formed by sections 9, 10 and 11, is caused to fold inwardly about score line 12.

As the container is carried from the point at which Fig. 11 is taken to the point at which Fig. 12 is taken.

the apex point of connection between bars 73 and 75 has been passed and the cover extensions arebeing acted upon by the inwardly inclined section 74a of the bar 74. The bar 76 will then be in contact with the outer face of cover 8, preferably at a point close to the score line 12. The downwardly and inwardly inclined bar 75,, which is virtually an extension of the bar 73, is in contact with the extended portion of the cover preferably at the approximate position of score line 14 between sections 10 and 11. As shown in Fig. 12, at this point in the travel of the container at least a portion of the length of the cover and extended section is firmly engaged between bars 76 and 74a, while the extended sections, substantially as a unit, begin to be folded down and toward the inner face of the main portion of the cover.

The guide bar 76 extends from a point rearwardly just beyond the apex juncture of the bars 73 and 75 on one side and the juncture of bar section 74 and extension 74a on the other side. The bar 76 is inclined inwardly, as shown in Fig. 3. It lies substantially in a horizontal plane somewhat above the plane in which bar 74 lies. In order to position the bar 76 studs are preferably welded to the bar at two places somewhat separated from its extremities and the ends of the studs are threaded and held adjustably in the frame of the machine in a manner similar to the arrangement of the end of bar 74, as indicated at 86.

As the container is carried from the point at which Fig. 12 is taken to the point at which Fig. 13 is taken it will pass beyond the end of bar section 74a. The position of bar 76 at this place causes the cover main portion to move further in the direction of closing and bar 75 is continuing to engage. the cover extended pertion at approximately the score line 14 between sections 10 and 11. The portions of bars and 76 are relatively close at this point causing the panel section 11- to approach the glued area on the under face of the closure main section where it is to be seated finally.

As the container is carried from the point at which Fig. 13 is taken to the point at which Fig. 14 is taken the inward inclination of bar 76 causes the cover to begin a downward swinging movement. As bar 75 is also inclined inwardly and downwardly the sections 10 and 11 of the cover extension will also swing downward, maintaining a spaced relationship.

After the downward swing of the covers has commenced the edges of the covers which carry the extensions come into contact with the curved front edges of guide plates 90, secured, one on each side of the central supporting memberv72. See Figs. 2 and 4. These guide plates are similar and througout the major portion of their lengths are straight and somewhat downwardly inclined in the direction of movement of the containers. The bars 76 preferably terminate a short distance rearwardly of the front edges of guide plates 90, and their function is taken over by the guide plates. It is apparent that as soon as the covers have swung inwardly to an inclination somewhat less than 90 they will be forced, as they move along beneath the downwardly inclined guide plates 90, 90, to move gradually toward their closed position.

The guide rods 75 preferably extend rearwardly a substantial distance beneath the guide plates 90 and are inclined downward in the direction of movement of the containers. As illustrated in Fig. 2, the guide bars are preferably approximately parallel to the plane of the guide plates. The rear end portions of bars 75 also are inclined inwardly toward the central supporting member 72. In the present construction the bars 75 terminate approximately midway of the length of the guide plates 90.

After the container has passed beneath the forward portions of the guide plates 90 and has moved to a point where the container closures have been swung down to a small angle with respect to the top edges of the container end walls the edge of extended section 9on the cover will come into contact with the central supporting member 72 which at this point also becomes a guide member. See Fig. 15. Moving contact of the cover edges at score lines 12 along the guide plates 90 added to the moving contact of the edge of the cover extension along score line 13 with the guide surface formed by the member 72 cause the sections 9 of the cover extension to remain at approximately right angles to the covers. Preferably the sections 9 will lie at an angle of somewhat less than 90 to the planes of their attached covers, as they will be in the completed construe tion of the cover reinforcing members.

As the folding of the parts of the cover reinforcing members tends to produce an outward thrust on the covers which in turn tends to bow out the cover hinge lines at their connection with side walls 5, 5, it is desirable to provide means to resist such outward deflection. For this purpose a number of small idler rollers 91, 91 are provided turning on vertical axes and located above the conveyer belts 27 to bear against the upper portions of the sides 5, 5 of the container.

As the container is moved from the point at which Fig. 15 is taken to the point at which Fig. 16 is taken the cover extension sections 10 and 11 have been flexed further upward by the rod 75, as viewed in Fig; 15, and the folded edge 13 is moved toward the inside of the angle formed by the cover and section 9. Thus the tapered edge portion of the reinforcingv rib is conditioned to enter the slot formed in the mandrel 57. Just as the edge 13 of the reinforcing rib begins to enter the slot in the mandrel the container cover will pass beyond the end of the guide rod 75.

Itis to be understood slot in the mandrel while the trailing portion is still infinanced by contact with the rod 75. As shown in Fig. 16, the reinforcing rib member on each cover has been forced part way into the slotted mandrel, one rib entering into each separate slot portion. At this point the section 11 and the glued area on the underside of the cover are approaching each other and will be in final contact as soon as the free edge portions of the reinforcing ribs have been forced fully into the slots in the mandrel.

The central supporting member 72 is carried on rods 79, 79 for vertical adjustment with respect to the conveycr for carrying the containers. This adjustment is conveniently effected by providing on member 72 a bracket member 93 into which the end of a threaded rod 94 is rotatably held. This threaded rod passes through a threaded part of a second bracket 95 carried by rod 79. By rotating the rod 94 the member 72 can be raised or lowered to a desired position.

It is preferable to adjust the member 72 so that the rear ends of guide plates 90 will cause the reinforcing rib members on the container to reach approximately their final position within the groove 58 of the mandrel with one rib element in each section of the groove.

As the containers are ejected from the conveyer formed by rollers 26 and lateral contacting belts 27, 27 the reinforcing rib members on the covers are completed and have been forced into the mandrel groove. The container is thus complete except for the fact that the adhesive to hold the section 11 against the under surface of the cover may not be completely set. It is desirable therefore to provide suitable hold-down means for retaining the cover and the reinforcing rib parts in position until the adhesive has thoroughly set. For this purpose a container receiving conveyer is preferably provided supported by suitable frame elements and including upper and lower endless belts 97 and 98 held in relatively fixed planes by idler rollers 99 and 100. The belts 97 and 98 pass over suitable pulleys 101 and 102, adapted to be driven by a source of motive power, not shown. The conveyer belts 97 and 98 are of such length that the adhesive will have adequate time to become set. When the container is discharged from this conveyer the mandrel will be removed and the container is then ready to receive contents.

It will be apparent that the machine according to the invention hereinabove described is capable of forming reinforcing ribs on container covers smoothly and continuously at relatively high speeds in a simple, efiicient and economical manner.

While the present description sets forth a preferred embodiment of the invention, numerous changes may be made in the construction without departing from the spirit of the invention, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description to indicate the scope of the invention.

I claim:

1. A machine for forming edge-reinforcing rib members on a hinged container cover at the outer edge remote from the cover hinge, the container cover being formed of foldable paperboard and having an extended edge portion on such outer edge formed from three relatively narrow rib-forming sections separated from each other and from such outer edge by parallel score lines, such machine comprising conveying means for carrying the container lengthwise along a predetermined path, means for guiding the cover and its associated edge portion, means operative as the container is conveyed along said path for folding the first rib-forming section joined to such outer edge into a raised position and somewhat inwardly inclined toward the cover hinge, additional means operative as the container is so conveyed for folding the second rib-forming section joined to the first such section into a position in which its edge remote from the juncture with such first section rests substantially against the inner surface of the cover and folding the third section joined to the second section into a position in which such third section lies substantially flat against the inner surface of the cover, the machine including means for applying adhesive to one of the last two contacting surfaces to cause the third section to adhere to the container cover.

2. In a machine for forming edge-reinforcing rib members on a hinged container cover at the outer edge remote from the cover hinge, the container cover being formed of foldable paperboard and having an extended edge portion on such outer edge formed from three relatively narrow rib-forming sections separated from each other and from such outer edge by parallel score lines, such machine comprising conveying means for carrying the container lengthwise along a predetermined path, means for guiding the cover and its associated edge por tion, means operative as the container is conveyed along said path for folding the first rib-forming section joined to such outer edge into a raised position, additional means operative as the container is so conveyed for folding the second rib-forming section joined to the first such section into a position in which its edge remote from the juncture with such first section rests substantially against the inner surface of the cover and for folding the third section joined to the second section into a position in which such third section lies substantially fiat against the inner surface of the cover, whereby such third section is in position adapting it to be secured readily to the cover.

3. A machine for forming edge-reinforcing rib members on a hinged container cover at the outer edge remote from the cover hinge, the container cover being formed of foldable paperboard and having an extended edge portion on such outer edge formed from three relatively narrow rib-forming sections separated from each other and from such outer edge by parallel score lines, such machine comprising conveying means for carrying the container lengthwise along a predetermined path, means for guiding the cover and its associated edge portion, means operative as the container is conveyed along said path for folding the first rib-forming section joined to such outer edge into a raised position and somewhat inwardly inclined toward the cover hinge, additional means operative as the container is so conveyed for folding the second rib-forming section joined to the first such section into a position in which its edge remote from the juncture with such first section rests substantially against the inner surface of the cover and folding the third section joined to the second section into a position in which such third section lies substantially flat against the inner surface of the cover, the machine including means for applying adhesive to one of the last two contacting surfaces to cause the third section to adhere to the container cover, a mandrel having a panel member formed with a lengthwise extending groove adapted to receive the apex portion of the completed edge-reinforcing rib, and means for retaining the apex portion of the min forcing rib within the groove to permit setting of the adhesive.

4. A machine for forming edge-reinforcing rib members on a hinged container cover at the outer edge remote from the cover hinge, the container cover being formed of foldable paperboard and having an extended edge portion on such outer edge formed from three relatively narrow rib-forming sections separated from each other and from such outer edge by parallel score lines, such machine comprising conveying means for carrying the container lengthwise along a predetermined path, means for guiding the cover and its associated edge portion progressively through a curved path from a laterally extended position to a position substantially flat at the top of the container, means operative as the container is conveyed along its path for folding the first rib-forming section joined to such outer edge into a raised position, additional means operative as the container is so conveyed for folding the second rib-forming section joined to the first such section into a position in which its edge remote from the juncture with such first section rests substantially against the inner surface of the cover and folding the third section joined to the second section into a position in which such third section lies substantially flat against the inner surface of the cover, the machine including means for applying adhesive to one of the last two contacting surfaces to cause the third section to adhere to the container cover, a mandrel adapted to be received inside the container and having a top panel member formed with a lengthwise extending groove adapted to receive the apex portion of the completed edge-reinforcing rib, and means for retaining the apex portion of the reinforcing rib within the groove to permit setting of the adhesive.

5. A machine for forming edge reinforcing rib members on hinged container covers located at the meeting edges of the covers which are remote from the cover hinges, the container covers being formed of foldable paperboard and each having an extended edge portion on such meeting edges formed from three relatively narrow rib-forming sections separated from each other and from the cover meeting edges by parallel score lines, such machine comprising conveying means for carrying the container lengthwise along a predetermined path, means for guiding each container cover and its associated edge portions progressively through a curved path from a laterally extended position to a position substantially flat at the top of the container, means operative as the container is conveyed along its path for folding the first ribforming section of each cover joined to the meeting edges into a position somewhat inwardly inclined toward the respective cover hinges, additional means operative as the container is so conveyed for folding each second rib-forming section joined to each respective first section into a position in which its edge remote from the juncture with such first section rests substantially against the inner surface of each respective cover and folding each third section joined to the second section into a position in which each third section lies substantially flat against the inner surface of each respective cover, the machine including means for applying adhesive to one of the last two contacting surfaces on each cover to cause the third sections to adhere to their respective covers, a mandrel adapted to be received into the container and having a top panel member formed with a lengthwise extending groove to receive the apex portions of the completed edge-reinforcing ribs, and means for retaining such apex portions of the reinforcing ribs within the mandrel groove as the container is conveyed to permit setting of adhesive between the covers and the respective third rib-forming sections.

6. A mandrel for use in the production of a reinforcing rib on a container cover which is formed of foldable paperboard with an extended edge portion providing three relatively narrow rib-forming sections separated from each other and from the cover edge by parallel score lines, such mandrel comprising a top panel, and vertical portions adapting it to fit within a container having such cover member, the top panel of the mandrel being formed with a groove to receive the apex portion of the two rib-forming sections next adjacent the cover edge, the portion of the top panel adjacent the groove serving to support the third and outer rib-forming section against the under side of the container cover, whereby such section can readily be secured to the container cover while the groove in the mandrel retains the two ribforming sections next adjacent the cover edge in angular relation.

No references cited. 

